Introduction: The co-occurrence of orthorexia nervosa and obsessive-compulsive disorder has been highlighted in numerous previous studies. While the associations between these two conditions are well established, the underlying mechanisms of this relationship remain relatively unexplored. The diagnostic criteria for both of those disorders mention the need for control as one of the main factors that play a key role in maintaining their symptoms.
Purpose: This study aims to examine the mediating role of beliefs about losing control in the relationship between obsessive-compulsive symptoms and orthorexia nervosa.


Methods: The sample consisted of 268 participants from the Polish general population, aged 18 to 75 years. We used the Polish versions of the Beliefs About Losing Control Inventory, the Obsessive-Compulsive Inventory-Revised and the Eating Habits Questionnaire.
Results: The results revealed a significant indirect effect of obsessive-compulsive symptoms on beliefs about losing control (b = 0.8792, t = 0.0622). Obsessive-compulsive symptoms turned out to have an insignificant direct effect on orthorexia nervosa (b = 0.400, t = 0.7889). Additionally, beliefs about losing control have shown a significant positive impact on orthorexia nervosa (b = 0.1100, t = 2.9100). Furthermore, the direct effect of obsessive-compulsive symptoms on orthorexia nervosa in the presence of the mediator (beliefs about losing control) was also found to be significant (b = 0.1490, p < 0.001).


Conclusions: The study highlights the significant mediating role of beliefs about losing control in the relationship between obsessive-compulsive symptoms and orthorexia nervosa. These findings may enhance our understanding of the underlying mechanisms of both disorders and offer valuable insights for developing more targeted and effective treatment approaches.